We announced a new communications product, Hangouts, in May 2013. Hangouts will replace Google Talk and does not support XMPP.
If your client properly implements XEP 0115, the Entity Capabilities extension, and identifies itself in the node attribute of the capabilities element, Google will be able to generate usage numbers for your client application. These numbers include no personal data other than the number of users using a chat client. We will periodically publish third-party client usage numbers on our Talkabout Blog with statistics for each unique node value.